Methyl iodide → (E)-8-(3-Bromostyryl)-1,3-diethyl-7-methylxanthine (6d)

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Compound g (2.5 g, 6.43 mmol) obtained in Reference Example 7 was dissolved in 20 ml of dimethylformamide. To the solution were added 2.22 g (16.1 mmol) of potassium carbonate and subsequently 0.8 ml (12.9 mmol) of methyl iodide, and the resulting mixture was stirred at 50° C. for 70 minutes. After cooling, insoluble matters were filtered off and water was added to the filtrate. The mixture was extracted three times with chloroform. The extract was washed three times with water and subsequently twice with a saturated aqueous solution of sodium chloride, and dried over anhydrous sodium sulfate. Evaporation under reduced pressure gave 2.37 g (yield 92%) of crude Compound h as a yellow solid, which was further recrystallized from cyctohexane/toluene to give Compound h as a yellow powder.

Herkunft & Nachweise